Volvo VNL Break Lights not working

Since you lost both truck and trailer I would check the air pressure sensor on the firewall pass-thru. It is on one of the push-locs on the pass-thru. You have to take the kick panel out on the left side by the pedals. The trailer has it's own fuse, and should be labeled as such. I can't remember the fuse number. Hope this helps.

 

ouh, Volvo use no fuses for light, they use LCM (MID 216) with "smart" MOSFETs. so check LCM codes and you can see is the wire broken ore short. If no LCM codes, check brake switch. People thing that brake switch is inside cab pedal mounted, but really it is VECU switch, brake light switch is located on pass side usually under the sleeper. It is 0.4 bar pressure switch mounted in brake air line and when brake pressure is over 0.4 BAR it is short. It is connected with twist connector and terminals ore wires may be corroded.

 

Yeah. The computers control everything from headlights to tail lights.

gone are the days of resetable circuit breakers and fuses.

 

Well you guys answered my question..so I guess I'm taking it to the shop. I couldn't find a fuse for that either.
Thanks !!

 

"Break" lights? Wasn't aware any vehicle came with "Break" lights.

 

A driver is supposed to turn them on when they're on their 30 min. or 10 hour break to let the DOT know not to disturb them.